Method of cinematographic television



April 5, 1938.

-D. VON. MlHALY v METHOD OF CINEMATOGRAPHIC TELEVISION Filed March 3,1930 Patented Apr. 5, 1938 UNITED STATES METHOD or CINEMATOGRAPHIG TELE-VISI Dnes von Mihaly, Berlin-Wilmersdorf, Germany, assignor to TelehorAktien Gesellschaft, Berlin-Charlottenburg, Germany Application. March3,.

In Germany 2 Claims.

This invention relates to an apparatus for cinematographic television,the object of the invention being to render possible the transmission ofthe usual cinematographic pictures by means of television apparatus.

Television apparatus as hitherto proposed allow pictures to betransmitted which have a comparatively small number of details, forinstance heads. It is, however, impossible to transmit groups of personsor landscapes or the like sufficiently clear and so that thereproduction should contain a suflicient number of details.

The present invention enables the transmission of the usualcinematographic film containing pictures which, owing to their greatnumber of details could not hitherto be transmitted, to be efiectedthereby avoiding the necessity of selecting a particular strip of film,by this that only the essential parts of the picture are transmitted andfor this purpose they are projected on an enlarged scale into thetelevision apparatus, while the parts which are secondary as regards thescene in question are not transmitted.

The invention essentially consists in this that the cinematographicapparatus which projects the cinematographic picture on the pictureopening of the picture scanning device is adjusted to difierentenlargements and the picture in the picture opening is displaceablelaterally in an upward and in a downward direction.

The invention is illustrated diagrammatically and by way of example inthe accompanying drawing, in which:

Figure 1 is a television cinematographic transmitter according to theinvention.

Figure 2 is a view of a portion of the picture scanning device with thepicture opening on an enlarged scale and seen in the direction of thearrow I in Figure 1.

Figure 3 is a side view of another form of construction.

Figure 4 is a front view of a modification, and

Figure 5 is a side view of another form of construction.

Referring to Figures 1 and 2, 2 is a picture scanning device in the formof a Nipkow disc which is driven in a known manner by a synchronousmotor, for instance by a phonic wheel 32. 3 is a cinematographicprojecting apparatus of any desired construction which projects thepicture of the cinematographic film to be transmitted on the pictureopening 4 of the picture scanning device.

A lens 5 and the photoelectric cell 6 are mounted behind the Nipkowdisc. The photoelectric 1930, Serial No. 432,991 March:5, 1929 currentsand their fluctuations which correspond to the fluctuations in thebrightness of the picture elements are led to an amplifier 1 andtherefrom to a wireless transmitter 8.

The cinematographic projector 3 can be adjusted by means of a hand wheel9 in a vertical direction and by means of a hand wheel H1 in a lateraldirection with respect to the picture opening 4; at the same time theprojector can be displaced longitudinally on rails H in the direction ofthe optical axis. In this axial displacement the adjustment of theobjective l2 of the projection apparatus is subsequently additionallyregulated by means of the screw I3.

If, for instance, a scene is transmitted containing a number of personspresent at the same time and which would contain too many picturedetails for the transmission, the cinematographic apparatus can bedisplaced in the direction of the optical axis, as well as verticallyand laterally, the sharpness being subsequently regulated, in such amanner that only the essential parts of the picture, for instance twopersons are projected on the picture opening 4 and are transmitted,which parts are transmitted and which parts are avoided can be easilydetermined by making the Nipkow disc 2 and the covering frame M whichsurrounds the picture opening 4 whitish.

In the form of construction illustrated in Figure 3 the adjustment ofthe objective I2 is effected automatically by this that a toothed bar I5is provided between the rails H which supports the projector 3 and witha toothed wheel I'l secured to the shaft I6 engages with the said rackl5. When the projector 3 is axially displaced the toothed wheel I1 isrotated by the stationary rack l5 whereby the adjustment of theobjective is effected automatically through the intermediary of thebevel wheels l8.

In the form of construction illustrated in Figure 4, objectives [9, 20,and 2| are mounted in a rotary head 22 being adjusted to differentdistances and three corresponding indices are provided on the guidingrails corresponding to the three different adjustments. Thecinematographic apparatus is moved in the direction of the optical axisinto the position corresponding to one of the said three indices and theobjectives i9, 20, or 2| corresponding to the respective index isbrought into the operative position.

In the example illustrated in Figure 5 a sharp adjustment is effectedautomatically by this that the mechanical part of the projector 23 isstationary whilst the lamp casing 24 with the condenser 25 and theobjective 26 of the projector is displaced along the rails II in thedirection of the optical axis. A stationary screw nut 27 is provided onthe lamp casing 24, whilst a stationary screw nut 28 is secured to theobjective 26 of the projector, which screw nuts are mounted on a commonscrew-threaded spindle 29, the end of the spindle on which the screw nut28 is mounted being provided with a left hand screw thread 30 and theend provided with the screw 1. In combination, a scanning device foranalyzing the varying intensities of light and shadow upon cyclicallyrecurring series of elemental areas of a subject of which the image isdesired, an optical system associated with the scanning device, movablemeans for producing relative movement between the subject oftransmission and the scanning device, and automatic means operable uponmovement of the movable means for maintaining in focus the opticalsystem used in the scanning operation.

2. In a television system, a scanning device for analyzing varyingintensities of light and shadow on successive elemental areas of asubject of which an image is to be transmitted, an optical systemassociated with the scanning device, and means for moving the opticalsystem to auto- 'matically maintain it in focus upon relative movementof the scanning device and the subject scanned.

' DENEs voN MIHALY.

